Abstract: Semiconductor device and the manufacturing method thereof are disclosed herein. An exemplary semiconductor device comprises a fin disposed over a substrate, a gate structure disposed over a channel region of the fin, such that the gate structure traverses source/drain regions of the fin, a device-level interlayer dielectric (ILD) layer of a multi-layer interconnect structure disposed over the substrate, wherein the device-level ILD layer includes a first dielectric layer, a second dielectric layer disposed over the first dielectric layer, and a third dielectric layer disposed over the second dielectric layer, wherein a material of the third dielectric layer is different than a material of the second dielectric layer and a material of the first dielectric layer. The semiconductor device further comprises a gate contact to the gate structure disposed in the device-level ILD layer and a source/drain contact to the source/drain regions disposed in the device-level ILD layer.